About 50% of the adult population will develop varicose veins or smaller visible veins called "spider" veins. Genetics plays a big role in the development of these veins. Although it's not possible to change the genes your parents gave you, many other factors also affect the formation and severity of these veins. Changing elements of your lifestyle and everyday activities can make a difference to your veins.

Lifestyle factors in the development of varicose veins:

genetics

standing for long periods

binding clothing

chronic constipation

birth control pills/estrogen replacement therapy

high-heeled shoes

menstrual cycle

weak leg muscles

heat

strenuous exercise

How veins work

To understand why the different lifestyle factors make such an impact, it's important to have a basic understanding of how veins work.

The main purpose of leg veins is to return blood up the legs to the heart. The blood is pumped up the legs by muscle contraction and breathing. So, when you walk or move, the venous blood moves. And when you stand still, so does the blood.

The weight of all the blood in your legs is very heavy - so heavy, in fact, you would think it would drain down to your feet when you stand still. The veins prevent this from happening. Hundreds of small valves within the leg veins shut when you stand still. These valves keep the blood in place and stop it from running back down to your feet. When you start to walk again, the valves open up and the blood is pumped toward the heart.

Varicose veins result from expanded vein walls and damaged valves

Although the exact cause of varicose veins is unknown, we do know that the walls of the veins can expand and valves can be damaged. This damage can happen when the blood is prevented from moving out of the legs as it should. Since the weight of the blood is so heavy, the valves are able to hold back the downward flow of blood for only a limited time. Then the vein wall gradually starts to expand. The valves no longer have a nice, tight fit, and blood starts to move down the leg. As more valves become damaged, more blood is allowed to pool in the vein, and it starts to become visible to the human eye. This is what we call a varicose vein. When you have this type of vein you may also have symptoms of tiredness and "heaviness."

Roxanne Hallgren, RN in association with the MediResource Clinical Team